High Current PCBs Dr. Christoph Lehnberger ANDUS ELECTRONIC GmbH, Berlin 1st International Conference September 28th - 29th, 2011 Nuremberg, Germany Profile of : Our Motto
Profile of : Our Capabilities Multi Layer / HDI RF / Impedance Flexible PCBs Rigid Flex Electronics Cooling Production High-End PCBs and Express Prototypes Location Berlin Foundation 1969 Employees 64 Service Technology Development and Advice Content 1 Overview of Power PCBs
Content 1 Overview of Power PCBs 1 Overview of Power PCBs Standard PCBs with increased copper thickness up to 400 µm Leveling conductor gaps by special filling paste to obtain flat surfaces Iceberg Technology with different copper thicknesses on one layer technology with embedded massive copper busbars today s topic
1 Overview of Power PCBs (continued) Wirelaid Technology with embedded wires in multilayer Selective areas with incorporated thick copper PCB (Schweizer El. AG) IMS substrates: e.g. special material by ANDUS Goal: 320x LED 320x 1W External heat sink Embedded heat sink Content 1 Overview of Power PCBs
Efficient handling of high currents combined with electronic control There are a number of PCB technologies for high currents. Most methods show insufficient conductor cross sections between PCB layers and components or cables. The new technology supplies maximum conductor cross section at any interface.
Additional requirements:! Standard SMD production processes! High degree of freedom for electronic design! Reduction of mounting effort, material and time Content 1 Overview of Power PCBs
Embedded copper bars Idea: Integration of copper parts of 1 mm thickness into PCBs cross section Production steps ❶ Preparation of copper parts by etching, milling or punching, depending on quantity, size and shape ❷ Milling frames ❸ Multilayer lamination Final production: drilling, plating, patterning, coating, milling, testing. ❶ ❷ ❸
General design rules for copper bars, to be adapted to any single project. A Line width B Clearance C Edge distance D Minimum Drill 2.0 mm 2.0 mm 0 mm 0.8 mm D B A C Content 1 Overview of Power PCBs
Variation 1: Direct contact to SMT components Advantages: - direct high current access to SMD components - direct heat sink contact - maximum cross section of any interconnect Variation 1 (continued) Example: 16 parallel D2Paks
Variation 2: Peripheral leads Copper bars can be lead out of PCBs for easier connection reasons. Variation 3: Reliable copper inlays Insertion of copper parts during multilayer process with access from both sides of the PCB. Freedom of location and size of inlay:
Variation 3 (continued): Reliable copper inlays Conventional inlay Embedded inlay Mechanical stress when coin is fitted in. No contact to electrical layers. Variation 4: Single sided version Heat sink for direct cooling without isolation gap. Especially for high power LEDs up to 10W.
Content 1 Overview of Power PCBs Automotive application
Planar transformer Automotive application: Wire bonding of bare chips onto uncovered copper bars.
2x 1 mm copper layers Avionics (sorry, confidential)
Main Message: Save mounting material, space and time before after re-design sorry, just wildcard pictures Thank you for your attention! High currents by busbars in PCBs ANDUS ELECTRONIC GmbH Berlin www.andus.de Dr. Christoph Lehnberger c.lehnberger@andus.de +49 30 610006-81